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Chinese Journal of Chemistry 2011年第1期29卷 178-184页

作者： Feng, Yunfei Yuan, Deyun Wang, Ju li, Baolong li, haiyan Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Material Science Soochow University Suzhou Jiangsu 215123 China

The reaction of 4-amino-3,5-bis（imidazol-l-ylmethyl）-1,2,4-triazole （abit） and manganese（Ⅱ） salts yields four coordination polymers {[Mn（abit）3]（C104）z}n （1）, {[Mn（abit）3]（PF6）2},, （2）, [Mn（abit）（dca）2（H2O）2],, （3a） and [Mn（abit）（dca）2（H2O）2]n （3b）. Compounds 1 and 2 are one-dimensional triple-stranded chain. Compounds 3a and 3b are polymorphous and construct one-dimensional single chain. The conformational analysis is performed. The thermal properties have been investigated.

关键词： manganese complex polymorphism crystal engineering coordination polymer. 4-amino-3,5-bis(imidazol-l-ylmethyl)- 1,2,4-triazole

Bioglass enhances the production of exosomes and improves their capability of promoting vascularization

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Bioactive Materials 2021年第3期6卷 823-835页

作者： Zhi Wu Dan He haiyan li Shanghai Jiao Tong University Affiliated Sixth People's Hospital School of Biomedical EngineeringShanghai Jiao Tong University1954 Huashan RoadShanghai200030China Med-X Research Institute School of Biomedical EngineeringShanghai Jiao Tong University1954 Huashan RoadShanghai200030China

Recently,exosomes have been extensively applied in tissue ***,their practical applications are severely restricted by the limited exosome secretion capability of ***,developing strategies to enhance the production of exosomes and improve their biological function attracts great *** have shown that biomaterials can significantly enhance the paracrine effects of cells and exosomes are the main signal carriers of intercellular paracrine communication,thus biomaterials are considered to affect the exosome secretion of cells and their biological *** this study,a widely recognized biomaterial,45S5 Bioglass®(BG),is used to create a mild and cell-friendly microenvironment for mesenchymal stem cells(MSCs)with its ion *** showed that BG ion products can significantly improve exosome production of MSCs by upregulating the expression of neutral sphingomyelinase-2(nSMase2)and Rab27a which enhanced the nSMases and Rab GTPases pathways,***,microRNA analysis indicates that BG ion products can modulate the cargoes of MSCs-derived exosomes by decreasing microRNA-342-5p level while increasing microRNA-1290 ***,the function of exosomes is modified as their capabilities of promoting the vascularization of endothelial cells and facilitating the intradermal angiogenesis are *** together,BG ion products are confirmed to enhance exosome production and simultaneously improve exosome function,suggesting a feasible approach to improve the practical application of exosomes in regenerative medicine.

关键词： Exosomes Bioglass ion products Vascularization Regenerative medicine

Mineral magnetic properties of surface sediments at Bei’anhe, Beijing, and its environmental significance

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Chinese Science Bulletin 2008年第16期53卷 2536-2546页

作者： WANG HongQiang ZHANG ShiHong li haiyan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Institute of Geophysics China Earthquake Administration Beijing 100081 China

A multiparameter investigation of surface sediments from the Bei’anhe section (Beijing) has been con- ducted using environmental magnetic approaches. The studied sedimentary sequence consists of pluvial and lacustrine silts and clay of the Holocene age. Magnetite, hematite and pyrrhotite were iden- tified as the dominant magnetic minerals. The mineral magnetic characteristics are considered to re- flect the Holocene paleoenvironmental processes of the studied area, which are different from the mineral magnetic properties of typical polluted sections reported in the Beijing area. The low-field magnetic susceptibility and saturated isothermal remanence magnetization of the section decrease gradually with increasing depth. This indicates that the concentration of magnetic minerals in the strata decreases down the section. Values of interparametric ratios, such as ARM/SIRM, χARM/χ and SIRM/χ, gradually increase with increasing depth, which indicates a down-section decreasing trend in the magnetic grain size of the sediments. Pyrrhotite occurs below the depth of 22 cm, suggesting the ex- istence of redox interface. The magnetic variations of the Bei’anhe surface sediments might be con- trolled by two geological processes: reductive diagenesis and pedogenesis. Our findings may have provided a reference point for magnetic investigation of polluted surface sediments in the Beijing area.

关键词：矿石磁性表面沉积物环境

Synthesis of Nano-ZSM-5 in Ultra-Concentrated System and Its Performance in Diesel Hydrodewaxing

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China Petroleum Processing & Petrochemical Technology 2016年第4期18卷 25-31页

作者： Qin lihong li haiyan li Jun Sun Famin china university of petroleum Beijing102249 daqing chemical research center petrochemical research institutepetrochina company limitedDaqing163714 daqing petrochemical company construction company petrochina company limitedDaqing163714

Nanocrystalline ZSM-5(with a crystal size in the range of 20—30 nm) has been synthesized in only 20 h via the crystallization of ultra-concentrated homogeneous synthesis mixtures. The influence of low water content, use of compound surfactant, a proper crystallization time and SiO_2/Al_2O_3 molar ratio on the properties of the final nanocrystalline ZSM-5 has been studied. Especially, the use of compound surfactant has influenced some properties of nano-ZSM such as the morphology, crystal size and crystallization greatly. The nano-ZSM-5 zeolite was investigated using XRD, BET, SEM, NH_3-TPD, and other techniques. The evaluation results in a 200-mL hydrogenation unit indicated that the synthesized nano-ZSM-5 had excellent catalytic performance in diesel hydrodewaxing.

关键词： ultra-concentrated system nano-ZSM-5 diesel hydrodewaxing

Enantioselective Synthesis of Optically Active Bis(β-hydroxy) Sulfones through Asymmetric Hydrogenation of Corresponding Ketones Catalyzed by a Chiral Cationic Ruthenium Diamine Catalyst

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Chinese Journal of Chemistry 2014年第8期32卷 803-813页

作者： Xiaofei Huang Min Zhao Naikai li haiyan li Jie li Xingwang Wang Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical EngineeringSuzhou UniversitySuzhouJiangsu215123 China Shanghai Institute of Measurement and Testing Technology Shanghai 201203China

Chiral molecules containing sulfonyl and 1,5-diol moieties are useful synthetic blocks for various asymmetric transformations.A protocol has been developed for the enantioselective synthesis of optically active bis(β-hydroxy)sulfones catalyzed by a chiral cationic ruthenium diamine catalyst.A series of bis(β-hydroxy)sulfones have been obtained in excellent yields(up to 99%)with excellent enantioselectivities(up to 99%)as well as good diastereoselectivities(up to 99∶1).

关键词： asymmetric catalysis hydrogenation ruthenium sulfone 1 5-diol

Establishment of A Simple and Efficient Agrobacterium-mediated Genetic Transformation System to Chinese Cabbage(Brassica rapa ***)

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Horticultural Plant Journal 2021年第2期7卷 117-128页

作者： Xiaonan li haiyan li Yuzhu Zhao Peixuan Zong Zongxiang Zhan Zhongyun Piao Department of Horticulture Shenyang Agricultural UniversityShenyangLiaoning 110866China

Chinese cabbage,belonging to Brassica rapa species,is an important vegetable in Eastern *** is well known that Chinese cabbage is quite recalcitrant to genetic transformation and the transgenic frequency is generally *** lack of an efficient and stable genetic transformation system for Chinese cabbage has largely limited related gene functional *** this study,we firstly developed a regeneration system for Chinese cabbage by optimizing numerous factors,with 93.50%regeneration rate on *** on this,a simple and efficient Agrobacteriummediated genetic transformation methodwas established,without pre-culture procedure and concentration adjustment of hormone and AgNO_(3) in co-cultivation and selection *** this system,transformants could be obtained within 3.5–4.0 *** transformation frequency is up to 10.83%.The establishment of this simple and efficient genetic transformation method paved the way for further gene editing and functional studies in Chinese cabbage.

关键词： Chinese cabbage Agrobacterium tumefaciens genetic transformation

Nickel/Quinim Enabled Asymmetric Carbamoyl-Acylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2023年第14期41卷 1673-1678页

作者： Xianqing Wu haiyan li Feng He Jingping Qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China

Transition metal-catalyzed difunctionalization of tethered alkene has emerged as a prevailing tool for the expedient construction of synthetically valuable cyclic ***,most efforts have been devoted to the reaction of styrene-type substrates due to their rigid scaffold and high *** respect to the difunctionalization of nonaromatic tethered olefin,especially the mono-substituted alkene,still remains largely ***,we disclose a nickel/Quinim complex and TBADT-cocatalyzed asymmetric carbamoyl-acylation of unactivated alkene tethered on nonaromatic carbamoyl chlorides with diverse *** reaction exhibits broad substrate scope with good functional group tolerance,as well as high reaction efficiency and *** monosubstituted and 1,1-substituted alkenes can work well with either aliphatic or aromatic aldehydes under the current protocol,providing convenient access to an array of medicinally useful chiralγ-lactams derivatives bearing a convertible acyl *** reaction showcases more application possibilities of the chiral Quinim ligand in the future asymmetric catalytic transformations.

关键词： Nickel Quinim ligand Lactams Asymmetric catalysis Alkenes

Controlled growth of ZnO nanorods by polymer template and their photoluminescence properties

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Science China(Technological Sciences) 2009年第4期52卷 888-892页

作者： li JiangYong li Lan XU JianPing ZHANG XiaoSong li haiyan ZHUANG JinYan Institute of Material Physics Tianjin University of Technology Tianjin Key Laboratory for Optoelectronic Materials and Devices Key Laboratory of Display Materials and Photoelectric Devices of Ministry of EducationTianjin 300384China Institute of Modern Optics Nankai UniversityTianjin 300171China School of Electronic and Information Engineering Tianjin UniversityTianjin 300172China

A large amount of one-dimensional ZnO nanorods with diameters in 15―50 nm aligned in radial cluster were successfully synthesized by polar polymer polyvinyl alcohol (PVA) as soft-template. The growth of ZnO nanorods was controlled by changing annealing temperature. The evolution of the morphology and microstructure was investigated by scanning electron microscope, transmission electron micro- scope and X-ray diffraction. It is shown that ZnO nanorods tend to be uniform and the crystallization is gradually improved with the temperature increasing from 400℃ to 700℃. The photoluminescence spectra of products show a strong ultra violet emission and relatively weak defect emissions. The sharp strong emission peak at 354 nm owing to the inter-band transition indicates the extraordinary photoluminescence property of ZnO nanorods.

关键词： ZnO nanorods polymer soft-template PVA photoluminescence spectrum

Surface Functionalized Carbon Nanofibers and Their Effect on the Dispersion and Tribological Property of Epoxy Nanocomposites

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1219-1225页

作者：朱艳吉汪怀远 li haiyan ZHU Jiahua College of Chemistry and Chemical Engineering Northeast Petroleum University Chemical and Biomolecula r Engineering The University of Akron

Surface functionalization of carbon nanofibers（CNFs） was carried out, i e, CNFs were firstly oxidized and then the surface was silanized by 3-Aminopropyltriethoxysilane（APTES） via an assembly method. A new kind of high wear resistance s-CNFs/epoxy composite was fabricated by in-situ reaction. FTIR spectroscopy was used to detect the changes of the functional groups produced by silane on the surface of CNFs. The tribological properties and microstructures of modified and unmodified CNFs/epoxy composites were studied, respectively. The expremental results indicate that APTES is covalently linked to the surface of CNFs successfully and improves the dispersion of CNF in epoxy matrix. The friction coefficients and the wear rates of s-CNFs/epoxy composites are evidently lower than those of u-CNFs/epoxy composites under the same loads. Investigations also indicate that abrasive wear is the main wear mechanism for u-CNFs/epoxy composite, with slight adhesive wear for s-CNFs/epoxy composite under the same sliding wear condition.

关键词： polymer-matrix composites carbon nanofibers surfaces functionalization friction and wear morphology

Rock-magnetic properties of Neogene sediments, northern flank of Tianshan Mountains

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Science China Earth Sciences 2007年第4期50卷 544-554页

作者： li ChuanXin GUO ZhaoJie MENG ZiFang li haiyan ZHANG ZhiCheng WU ChaoDong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education(Peking University)Beijing 100871China Lanzhou Institute of Geology Chinese Academy of SciencesLanzhou 730000China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

Analyses of rock-magnetic properties of Neogene sediments of the Taxihe section, northern Tianshan Mountains, show that the section can be classified into three categories including lacustrine facies, fluvial facies and alluvial facies, which correspond to the lower, middle and upper of the Taxihe section respectively. The magnetic minerals of the lacustrine facies may be affected by the process of weath- ering, lithogenesis and biolithogenesis besides the source of the sediments. The natural remanence intensities are between 10-3 A/m and 10-2 A/m. The minerals are dominated by magnetite and the high coercive magnetic mineral may be goethite. The magnetic grains are the mixture of PSD+SD or SD+SP. The natural remanence intensities of the strata of fluvial facies are between 10-2 A/m and 10-1 A/m, about ten times that of the lacustrine facies. The magnetic minerals are mainly magnetite and hematite, and the magnetic grains are mainly PSD. The characteristic remanence (ChRM) carriers are magnetites. In the alluvial facies, the natural remanence intensities are mostly less than 1×10-2 A/m. The magnetic minerals of the series are dominated by magnetite and hematite, almost the same as the fluvial facies. But the difference is that most of the stepwise demagnetization can reveal two components and the ChRM carriers are hematites. The magnetic grains are PSD in terms of the hysteresis parameters.

关键词： Northern flank of Tianshan Mountains Neogene magnetic carrier IRM temperature-dependent susceptibility Day plot